Serious problem with keyboard response lag time

This problem is occuring with my brand-new Inspiron 1400 laptop, Windows XP Home Edition.

When using either the laptop's keyboard or the ViewSonic USB keyboard that I have, in any software I try, there are delays between the time that I press keys on the keyboard and the time the letters appear on the monitor.  These delays do not happen with every character I type, but they occur every few seconds and last for several seconds before clearing up again, then repeat.  This always happens whenever I use either keyboard, in any software.  The system has 2 GB of RAM and surely should be able to handle my keyboard input, my old Dell Inspiron with only 768 MB of RAM never had this problem.

This is extremely annoying and makes keyboarding very frustrating and difficult.  The problem appears as is there is a keyboard-entry buffer that is filling up or overloading, but the problem occurs no matter at what rate I type in the letters.  This happens even with only one application open (in fact, the problem is happening as I type in these words and I have nothing open on my system except Internet Explorer at your website).

The problem persists after system rebooting.  I ran Dell Diagnostics, both the PSA and the System Diagnostics - Extended Test. These diagnostics did not return any errors, neither on the memory nor on the keyboard nor anywhere else on the system.

Is this machine defective and do I need to replace it under the 30-day warranty, or is there a simple fix for this?  I can't find anything in the FAQ or Knowledge Base on this problem, and none of the new drivers for the 1400 seem to address this issue. 

This is utterly unacceptable, as I use the computer mainly for text work, and I will ask for a refund and buy a product from another company if this can't be fixed PDQ.